zephyr/kernel/include/nano_internal.h
Chunlin Han e9c9702818 kernel: add memory domain APIs
Add the following application-facing memory domain APIs:

k_mem_domain_init() - to initialize a memory domain
k_mem_domain_destroy() - to destroy a memory domain
k_mem_domain_add_partition() - to add a partition into a domain
k_mem_domain_remove_partition() - to remove a partition from a domain
k_mem_domain_add_thread() - to add a thread into a domain
k_mem_domain_remove_thread() - to remove a thread from a domain

A memory domain would contain some number of memory partitions.
A memory partition is a memory region (might be RAM, peripheral
registers, flash...) with specific attributes (access permission,
e.g. privileged read/write, unprivileged read-only, execute never...).
Memory partitions would be defined by set of MPU regions or MMU tables
underneath.
A thread could only belong to a single memory domain any point in time
but a memory domain could contain multiple threads.
Threads in the same memory domain would have the same access permission
to the memory partitions belong to the memory domain.

The memory domain APIs are used by unprivileged threads to share data
to the threads in the same memory and protect sensitive data from
threads outside their domain. It is not only for improving the security
but also useful for debugging (unexpected access would cause exception).

Jira: ZEP-2281

Signed-off-by: Chunlin Han <chunlin.han@linaro.org>
2017-09-29 16:48:53 -07:00

178 lines
4.9 KiB
C

/*
* Copyright (c) 2010-2012, 2014-2015 Wind River Systems, Inc.
*
* SPDX-License-Identifier: Apache-2.0
*/
/**
* @file
* @brief Architecture-independent private kernel APIs
*
* This file contains private kernel APIs that are not architecture-specific.
*/
#ifndef _NANO_INTERNAL__H_
#define _NANO_INTERNAL__H_
#include <kernel.h>
#define K_NUM_PRIORITIES \
(CONFIG_NUM_COOP_PRIORITIES + CONFIG_NUM_PREEMPT_PRIORITIES + 1)
#define K_NUM_PRIO_BITMAPS ((K_NUM_PRIORITIES + 31) >> 5)
#ifndef _ASMLANGUAGE
#ifdef __cplusplus
extern "C" {
#endif
/* Early boot functions */
void _bss_zero(void);
#ifdef CONFIG_XIP
void _data_copy(void);
#else
static inline void _data_copy(void)
{
/* Do nothing */
}
#endif
FUNC_NORETURN void _Cstart(void);
extern FUNC_NORETURN void _thread_entry(k_thread_entry_t entry,
void *p1, void *p2, void *p3);
/* Implemented by architectures. Only called from _setup_new_thread. */
extern void _new_thread(struct k_thread *thread, k_thread_stack_t pStack,
size_t stackSize, k_thread_entry_t entry,
void *p1, void *p2, void *p3,
int prio, unsigned int options);
extern void _setup_new_thread(struct k_thread *new_thread,
k_thread_stack_t stack, size_t stack_size,
k_thread_entry_t entry,
void *p1, void *p2, void *p3,
int prio, u32_t options);
/* context switching and scheduling-related routines */
extern unsigned int __swap(unsigned int key);
#ifdef CONFIG_TIMESLICING
extern void _update_time_slice_before_swap(void);
#endif
#ifdef CONFIG_STACK_SENTINEL
extern void _check_stack_sentinel(void);
#endif
static inline unsigned int _Swap(unsigned int key)
{
#ifdef CONFIG_STACK_SENTINEL
_check_stack_sentinel();
#endif
#ifdef CONFIG_TIMESLICING
_update_time_slice_before_swap();
#endif
return __swap(key);
}
#ifdef CONFIG_USERSPACE
/**
* @brief Get the maximum number of partitions for a memory domain
*
* A memory domain is a container data structure containing some number of
* memory partitions, where each partition represents a memory range with
* access policies.
*
* MMU-based systems don't have a limit here, but MPU-based systems will
* have an upper bound on how many different regions they can manage
* simultaneously.
*
* @return Max number of free regions, or -1 if there is no limit
*/
extern int _arch_mem_domain_max_partitions_get(void);
#endif
#ifdef CONFIG_USERSPACE
/**
* @brief Check memory region permissions
*
* Given a memory region, return whether the current memory management hardware
* configuration would allow a user thread to read/write that region. Used by
* system calls to validate buffers coming in from userspace.
*
* @param addr start address of the buffer
* @param size the size of the buffer
* @param write If nonzero, additionally check if the area is writable.
* Otherwise, just check if the memory can be read.
*
* @return nonzero if the permissions don't match.
*/
extern int _arch_buffer_validate(void *addr, size_t size, int write);
/**
* Perform a one-way transition from supervisor to kernel mode.
*
* Implementations of this function must do the following:
* - Reset the thread's stack pointer to a suitable initial value. We do not
* need any prior context since this is a one-way operation.
* - Set up any kernel stack region for the CPU to use during privilege
* elevation
* - Put the CPU in whatever its equivalent of user mode is
* - Transfer execution to _new_thread() passing along all the supplied
* arguments, in user mode.
*
* @param Entry point to start executing as a user thread
* @param p1 1st parameter to user thread
* @param p2 2nd parameter to user thread
* @param p3 3rd parameter to user thread
*/
extern FUNC_NORETURN
void _arch_user_mode_enter(k_thread_entry_t user_entry, void *p1, void *p2,
void *p3);
/**
* @brief Induce a kernel oops that appears to come from a specific location
*
* Normally, k_oops() generates an exception that appears to come from the
* call site of the k_oops() itself.
*
* However, when validating arguments to a system call, if there are problems
* we want the oops to appear to come from where the system call was invoked
* and not inside the validation function.
*
* @param ssf System call stack frame pointer. This gets passed as an argument
* to _k_syscall_handler_t functions and its contents are completely
* architecture specific.
*/
extern FUNC_NORETURN void _arch_syscall_oops(void *ssf);
#endif /* CONFIG_USERSPACE */
/* set and clear essential fiber/task flag */
extern void _thread_essential_set(void);
extern void _thread_essential_clear(void);
/* clean up when a thread is aborted */
#if defined(CONFIG_THREAD_MONITOR)
extern void _thread_monitor_exit(struct k_thread *thread);
#else
#define _thread_monitor_exit(thread) \
do {/* nothing */ \
} while (0)
#endif /* CONFIG_THREAD_MONITOR */
#ifdef __cplusplus
}
#endif
#endif /* _ASMLANGUAGE */
#endif /* _NANO_INTERNAL__H_ */